Tandem Base-Promoted Ring Opening/Brook Rearrangement/Allylic Alkylation of O-Silyl Cyanohydrins of β-Silyl-α,β-epoxyaldehydes.

Metalated O-silyl cyanohydrins of β-silyl-α,β-epoxyaldehyde have been found to serve as functionalized homoenolate equivalents by a tandem sequence involving a base-promoted ring opening of the epoxide, Brook rearrangement, and alkylation of the resulting allylic anion.